Loading data...

Impressum Privacy Policy

© 2026 TerraCollect

0.2.41

Minerals - Willemite | TerraCollect

Mineral - Willemite

WillemiteZn₂SiO₄

Chemical Properties

Mineral Class

Silicates

Toxicity

none

Formula

Zn₂SiO₄

Unit Cell

a=13.95 c=9.32 Z=18

Physical Properties

Hardness

5.5

Streak

white

Density

Heavy (3,5-6)

Optical Properties

Color

whiteredgreenbluecolorless

Birefringence

0.031

Luster

Vitreous

Transparency

translucent,

transparent

Pleochroism

Geomineralogical Properties

Crystal System

Composition

Elements

Mass

SiO₂

26.55

Al₂O₃

1.00

FeO

0.08

MnO

0.12

ZnO

72.11

MgO

0.13

New Jersey (Dana 1895)

Groups and Members

Phenakite-Group

Karten-Ebenen

Geologische KarteSatelliten Karte

Cleavage

Indistinct after {1120} and {0001}

Fracture

conchoidal,

uneven

Tenacity

Brittle

trigonal

Point Group

rhombohedral - 3

Space Group

R3 (148)

Habit

spherical, prismatic, spherulitic, tabular

Formation

Secondary, formed by metamorphic transformation or hydrothermal metasomatism of zinc deposits (e.g., sphalerite) with the addition of SiO₂ in a silicate-carbonate environment.

Paragenesis

Twinning

Rarity

Rather rare

Synonyms

Willemite